The countdown is on to determine who will be the best fighter of his generation.

Saturday's main event title fight at UFC 94 is shaping up as a battle between two countries. American B.J. Penn is stepping up to challenge Sportsnet's 2008 Canadian Athlete of the Year, Georges St. Pierre. Penn has been talking quite a bit of smack leading up to this bout and this time he did it right in front of GSP's face.

This bout between St. Pierre and Penn is an anomaly in combat sports. It is rare that two champions, in the prime of their careers, will actually step into the cage to battle each other. Lightweight champion Penn will be moving up to the welterweight division to challenge St. Pierre in this historic superfight. You can literally count on one hand the amount of times these fights happen in a lifetime.

Leading up to this bout, the UFC tried something new to promote a main event. They put together the "UFC Primetime" show, a stellar documentary type mini-series which profiled both fighters, in depth, while building serious hype for the fight. Penn was portrayed as a rich, trash-talking phenom whereas St. Pierre was depicted as a blue collar champion with something to prove.

With the UFC Primetime cameras no longer rolling, the trash talk has cooled off, but the mind games haven't stopped. During the customary stare-down after the UFC 94 press conference, Penn told GSP he will have to lose too much weight for this bout. GSP responded with a cordial invitation for Penn to find out on Saturday night.

With a large number of Canadian fans already making their way to Las Vegas, it's shaping up to be another Canada vs. USA showdown. According to Penn he fully expects a pro-GSP crowd with the Canadian voices drowning out the Americans.

For many, Saturday night cannot come soon enough, but for the two combatants who will do battle in the cage, the countdown is on to determine who will be the best fighter of his generation.